I'm having a problem compiling this flutter code. It throws me the following error: The following assertion was thrown building FutureBuilder(dirty, state: _FutureBuilderState#afa3f): A build function returned null. The offending widget is: FutureBuilder Build functions must never return null. To…
When playing with MySQL I noticed that if I run SELECT * FROM table WHERE !value; returns the same thing as SELECT * FROM table WHERE value IS NOT NULL; The table is "employees" and the column is "MiddleInitial" (strings).…
Okay I have a FlutterFire app and using Riverpod to manage the state of my app. I have a Listenable Provider named userProvider where I get the user data from Cloud Fierestore. Note that I have a Stream Provider which…
Good morning everyone and thank you in advance for any suggestions. I have written a small web application to perform simple searches in a stamps database using php and javascript. The server sends to the browser the whole database as…
my Final declaration check if it's null don't work in flutter if (extractedData == null) { return; } Future<void> fetchAndSetOrders() async { const url = 'https://flutter-update.firebaseio.com/orders.json'; final response = await http.get(url); final List<OrderItem> loadedOrders = []; final extractedData = json.decode(response.body)…
I have an table and I want to fill the null value with previous value order by date but there have an group too For example: Table X: Date Group value 1/1/2023 A null 2/1/2023 A Kevin 3/1/2023 A null…
I want to add conditional for image but it show an error on _setImage(), how to fix it? The body might complete normally, causing 'null' to be returned, but the return type, 'String', is a potentially non-nullable type. Try adding…
I need map the struct to create a JSON structure. The collector_id attribute in JSON should be able to take null value or int value. I hace the follow code: type purchaseInfo struct { CollectorID *int64 `json:"collector_id"` } func mapPurchaseInfo(collectorID…
I get this error in the StreamBuilder: Here's the code: import 'dart:async'; import 'package:firebase_database/firebase_database.dart'; import 'package:flutter/material.dart'; class NewCauseMenu extends StatefulWidget { String? area; NewCauseMenu(this.area, {super.key}); @override State<NewCauseMenu> createState() => _NewCauseMenuState(); } class _NewCauseMenuState extends State<NewCauseMenu> { final db = FirebaseDatabase.instance;…
import org.json.JSONObject; String someStringJsonData = "{"someKey": " + "null" + "}"; JSONObject someJsonObjectData = new JSONObject(someStringJsonData); Object someKey = someJsonObjectData.get("someKey"); if (null == someKey) { System.out.println("someKey is null"); } I have the above simple snippet of code. I would expect…